The chemical and physical characterization of crude, partially refined, and fully refined petroleum products is a common practice in the petroleum industry. Characterizations such as compositional and physical property determinations are used for a variety of purposes. One of their more important uses is when they are done in combination with hydrocarbon well testing to assist in optimizing oil production from a single or series of hydrocarbon wells. Another important use is during the transfer of crude petroleum oil, as occurs during the production, transport, refining, and sale of oil. The accurate determination of water content and validation of the amount of water in crude oil are particularly important during the taxation of crude oil and the sale of crude oil, where the owner or seller of the oil does not want to pay taxes on water and the customer does not want to pay the price of oil for water. For example, crude petroleum oil emerging from production wells can contain large amounts of water, ranging generally from about 1% to as high as 99% water. This value is known as the water cut (“WC”).